Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, generator, nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of the wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades directly or indirectly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
The typical configuration of a conventional rotor blade generally includes a root section, a blade tip, and a blade shell extending between the root section and blade tip. The blade shell generally defines the aerodynamic airfoil shape of the rotor blade and may be formed from a fiber-reinforced material, such as glass fiber, carbon fiber, or the like. Additionally, the blade shell is typically a composite design, being manufactured from separate shell components which are bonded together. To bond the shell components, a thick layer of adhesive is typically applied to one or both of the shell components. The shell components are then brought into contact with one another (e.g., by placing the shell components on top of each other) to form a thick adhesive bond line around the edge of the blade shell (i.e., the leading and trailing edges of the rotor blade).
The use of adhesive bonding to combine the shell components of the blade shell often leads to significant performance penalties, particularly with respect to the trailing edge of the rotor blade. For example, due to the layer of adhesive, the trailing edge is inherently thicker resulting in a reduction of the aerodynamic efficiency of the rotor blade. This increased thickness also generates additional pure tone noises during operation of the wind turbine. Moreover, exposed portions of the adhesive are often very sensitive to erosion occurring in the field, which can lead to a weakening of the bond between the shell components. Further, it is often very difficult to apply the adhesive in controlled amounts, which results in rotor blades with poor tolerances, varying trailing edge thicknesses, and reduced efficiencies.
Accordingly, there is a need for a trailing edge bonding cap for use with a wind turbine rotor blade that results in reduced performance penalties.